This invention relates generally to an assembly including an actuator device useful for electrically connecting or disconnecting electrical conductive members, such as electrical lines, circuitry and wires, and electrical switches associated with electrical conductive members. More particularly, the invention relates to an assembly including a pyrotechnic-based actuator device, such as for appropriately electrically disconnecting or connecting electrical systems, such as, for example, automotive electrical systems, upon receiving an electrical signal in response to a predetermined condition, such as, for example, a short circuit or an automobile collision.
Dimple motors have been developed as “mini-actuators.” A dimple motor is a self-contained, pyrotechnic actuator having a stamped concave, or dimpled, canister. The dimple motor can be actuated by an electrical signal that activates a pyrotechnic material stored or housed within the dimpled canister. The actuated pyrotechnic material produces reaction products that cause the dimpled, concave end of the dimple canister to “pop” outward, resulting in a convex shaped dimple canister end. A dimple motor typically has a short, limited stroke, i.e., the distance the dimpled surface extends, or “pops,” upon actuation, and thus dimple motors have typically had only limited application. The stroke of a dimple motor is dependant on the size of the dimpled canister containing the pyrotechnic material. A stroke to storage ratio is the ratio of stroke length to the size of the dimple canister storing the pyrotechnic material. Dimple motors typically have a low stroke to storage ratio, generally less than one.
As will be appreciated, the undesired or unintended rupture or opening of the canister or chamber containing the pyrotechnic material and/or the reaction products formed therein can result in the device failing to perform in the intended manner as well as an unintended release of the pyrotechnic material or the products formed thereby.
Actuator devices having bellow-like features have been developed to produce a motion with a generally longer stroke than available with typical dimple motors. Upon receiving an electric signal, a pyrotechnic material reacts to produce gas and/or pressure to cause a portion of the device to extend. In practice, such an actuator device must be made of a material of sufficiently high strength and thickness in order to avoid rupture upon reaction of the pyrotechnic material therein contained. As will be appreciated, such requirements can detrimentally impact either or both the cost and/or weight of such a component.
In this regards, automobile manufacturers have generally sought to minimize the weight of component parts, without sacrificing quality and safety.
Thus, there is a need for a lightweight, relatively inexpensive and efficient actuator device for appropriately electrically disconnecting or connecting automobile electrical systems, upon receiving an electrical signal in response to a predetermined condition, such as, for example, a short circuit or an automobile collision. In particular, there is a need for an actuator device assembly that allows an actuator device to be made of thinner and/or lighter weight materials and yet avoids undesired or unintended rupture. Further, there is a need for an assembly including an actuator device that, upon an electrical signal, can disengage an electrical switch, or otherwise sever an electrical conductive member. More particularly, there is also a need for an assembly including an actuator device for use in combination with automotive electrical systems, that, upon a predetermined condition such as a short circuit or a collision, will receive an electrical signal from a sensor and disengage, or electrically disconnect, an emergency power disengagement switch.